Drilling apparatus



H. C. JOHANSEN DRILLING APPARATUS Oct. 25, 1932.

Filed Nov. 17, 1926 2 Sheets-Sheet Oct. 25, 1932. H. c. .loHANsl-:N 1,834,716

DRILLING APPARATUS Filed Nov. 17, 1926 2 Sheets-Sheet 2 Zi-ovvien Patented Oct. 25, 1932 UNITED STATES PATENT OFFICE HARRY C. JOHANSEN, OF MICHIGAN CITY, INDIANA, ASSIGNOR TO SULLIVAN MACHINERY COMPANY, A CORPORATION 0F MASSACHUSETTS DRILLING APPARATUS Application led November 17, 1926. Serial No. 148,856.

This invention relates to drilling apparatus and more particularly, but not exclusively, to drilling apparatus of the type adapted for oil o1' gas Well drilling.

In drilling earth formations, especially in oil or gas well drilling, it is highly desirable to remove a core of all strata penetrated to show in exact sequence the various layers of rock and other material with the depth, thiclrness, and the character' of each, and its dip and Strike. To cut the .core in hard formations, a core drill of the hydraulically fed, rotary diamond type is utilized. However, when soft shales, gumbo, and other soft and caving strata is encountered and where cores may not be required, a ishtail or rotary bit with mud fluid is employed. Heretofore, in certain instances, separate drilling outfits or rigs were used when cutting hard torniations to obtain a core and for cutting in soft formations when no core was required.

An object of this invention is to provide an improved unitary and compact drilling .apparatus whereby a diamond core bit or ishtail bit may be selectively used for cutting in hard or soft formations Without the necessity of separate drilling outfits and costly auxiliary equipment. invention is to provide an improved unitary drillingr apparatus whereby the iishtail or rotary bit may be fed by means of the usual hoisting drum and cable when penetrating soft formations, or a hydraulic feed may be used when penetrating hard formations with the diamond bit and obtaining a. core. Still another object of this invention is to provide an improved grief stem and automatic grief stem chuck. These and other objects and advantages of this invention will, however, hereinafter more fully appear.

The invention is exemplified in the novel elements and combinations of elements hereinatte:` clearly described and pointed out in the appended claims.

In the accompanying drawings I have shown for purposes of illustration one form which the invention may assume in practice.

ln these drawings,-

Fig. 1 isa front elevational view ot the improved drilling apparatus, parts being vlowering of the drill rods.

Another' object of this shown in section to illustrate details of con struction.

Fig. 2 is an elevational view of a portion of the improved grief stem.

Fig. 3 is a transverse horizontal sectional view taken substantially on line 3 3 of Fig. 4.

Fig. 4 is an enlarged detail sectional view of the improved automatic grief stem chuck. Figs. 5, 6 and 7 are detail sectional views ot the improved chuck shown in Fig. 4.

Figs. 8 and 9 are detail sectional views illustrating the means for locking the collar and wedges in their released position.

In this illustrative embodiment of the invention there is shown a drilling outiit generally designated 1 and generally comprising a base structure 2 on which is mounted an engine 3 which rotates the drill rod, a feeding apparatus 4, and the hoisting mechanism 5, the latter being mounted just back of the feeding apparatus. The base 2 is slidably mounted on parallel guides 6 to enable the drilling apparatus to be moved bodily away from the drill hole during hoisting and The engine 2 is of the well known steam driven angle compound type and drives through suitable connections, not shown, the hoisting drum 7 and rotates the drill ro As shown, the feeding mechanism comprises a vertical cylinder 8 suitablyl supported on the base frame and in which a piston 9 is reciprocably mounted. Pressure fluid, herein water under pressure, is adapted to be conducted to the ends of the cylinder 8 above and below the piston 9 through suitable pipe connections 10 under the control of a manually operable. valve l1 in a well known manner. Rigidly secured to the piston 9 is a hollow rod 12 which extends downwardly through a stuiiing box 13 carried by the lower cylinder head and upwardly through a stutting box lll carried by the upper cylinder head. This rod carries at its upper end, a thrust head l5 of usual form and which carries hall thrust bearings 16. Inter'posed between these bearings is a thrust plate 17 rigidly secured to a rotatable hollow rod 18, herein a drive rod. Carried on the lower end of the drive rod 18 is an improved automatic grief stem chuck, generally designated '19, which will later be described` the latter cooperating w1th a drill or grief stem 2O 0f improved design, and by which the usual rod line is carried. The grief stem 20 carries at its upper end a usual water swivel 21 and lifting bail 22. As clearly shown in Fig. 1, the drive rod 18 is longitudinally grooved or fiuted, as at S23, and cooperating with these grooves or flutes are keys 24 carried by the hub of a bevel gear 25 of the rotation mechanism, the bevel gear being rotatably mounted within a bearing sleeve 26 suitably carried by the feed cylinder support. The rotation mechanism may include a plurality of predetermined speeds. Meshing with the bevel gear is a bevel pinion 27 through which the drive rod 18 is rotated by the engine 3. From the foregoing description it will be obvious that the drive rod may be raised and lowered through the hub of the bevel gear 25. while the same continuously rotates. It will also be obvious that the longitudinal thrust of the drive rod in either direction will be absorbed b the ball bearings 1G carried within the t rust head.

The improved automatic chuck 19 specilically comprises an upper part or member 28 threadedly connected, as at 29, to the lower end of the drive rod 18 as clearly shown in Fig. 4. In accordance with this embodi ment of the invention, interposed between the member 28 and a lower plate 30 are a plurality of distance pieces or keys 31, herein four, held in position by bolts 32 engaging the lower plate 30 and threadedly connected to the top member 28. These distance pieces are used as part of the chuck body and also fit in grooves or flutes 33 formed in and extending longitudinally of the grief stem 20. From the foregoing it will be evident that the drive rod and the members 28, 30 and 31 rotate together and due to the cooperation of the parts 31 with the longitudinal grooves 33 in the grief stem, the latter also is rotated therewith. There is sufficient clearance between the parts 31 and the grooves 33 to permit free longitudinal movement of the grief stem 20 relative thereto in a manner to be later described. As clearly shown in Fig. 2, the grief stem 20 has formed thereon around its circumference a series of grooves or teeth 34, herein six, and each series of grooves is spaced apart longitudinally of the grief stem a distance to correspond with the travel of feed of the feed piston 9. Disposed in the spaces between the parts 31 'of the chuck are jaws 35 and these jaws are slidably 'guided at their lower ends within radial grooves 36 formed in the upper surface of the lower plate 30. rIhe inner sides o f these jaws have each formed thereon a series of teeth 37 which interengage or mesh with the circumferentially extending grooves or teeth 34 formed on the grief stem 20. The teeth 37 of the chuck interlocking with the grooves in the grief stem 20 positively connect the grief stem to the feed piston 9 and thereby prevent any slipping between the chuck jaws 35 and the grief stem. These toothed jaws are used when drilling with the hydraulic feed and during drilling with the diamond bit to hold the load or weight of the drill rods or may be disengaged from the grief stem when using the hoisting drum and cable to feed with the fishtail bit in soft formations, as will hereinafter be described. To operate these jaws 35, a collar 38 is provided which fits around or surrounds the body of the chuck. As illustrated, this collar has four recesses 39 within which the jaws project, and the bottoms on these recesses are tapered, as at 40, and cooperate with the tapered outer faces 41 of the' jaws. The jaws 35 have formed thereon on one side thereof longitudinally extending grooves 42 disposed parallel with the tapered faces 41 and with' these grooves, blocks 43 cooperate, these blocks being carried by the depending flange of the collar 38. A stop pin 43a is carried by the member 28 for preventing excessive upward movement of the collar 38. It will be evident that when the collar 38 is lifted uwardly, the blocks 43 move within the grooves 42 1n one side of the jaws, consequently causing the latter to move outwardly to release the locking engagement of the teeth on the jaws and the grief stem. Then the collar` is released and allowed to slide downwardly, the tapered surfaces and 41 on the collar and jaws will cause the jaws to be forced inwardly and when the grooves 34 on the grief stem are opposite to the grooves in the jaws, the collar will con'- tinue to move downwardly by gravity wholly without manual intervention until the jaws are automatically locked to the stem. Improved means is also provided for locking the collar 38 and the jaws 35 respectively in their raised and released position and such means comprises vertical pins 44 carried within recesses 45 in the collar 38 and rigidly secured to the latter and these pins are adapted to cooperate with transverse, straight slots 46 formed in the upper surfaces of the jaws 35. The recesses 45 extend laterally of the recesses 39 in the collar (see Fig. 7). When the collar 38 is in its upper position (see Figs. 5, 8 and 9) and slightly turned, the wedges enter the recesses 45 and the pins 44 engage the slots 46 in the jaws, consequently preventing downward movement of the collar, and thereby holding the jaws in their outer or released position away from the grief stem.

The operation of the improved drilling apparatus is as follows: When a hard formation is encountered and it is desired to obtain a core, the feed piston is moved to its uppermost position by hydraulic pressure lll5 lll)

Vwithin the cylinder 8. YThe collar 38 is then slightly turned, releasing the locking pins 44 from the transverse slots 46 in the jaws, thereby permitting the collar to move downwardly and consequently the jaws to move inwardly. Prior to the engagement of the automatic chuck with the grief stem, the latter and the rod line carried thereby are held suspended by means of the hoisting cable wound on the hoisting drum 7, the hoisting cable` passing upwardly from the hoisting drum around the usual pulley blocks carried at the top of the well derrick in a well known manner, the drop line of the cable carrying a hook which is connected to the lifting bail 22 at the top of the grief stem. After the release of the locking means for the collar and jaws, the hoisting drum is so operated as to permit slight longitudinal movement of the grief stem, the grief stem moving through the chuck until the grooves 34 formed thereon are opposite the teeth 37 of the jaws. The collar 38 will then continue to move downwardly by grave ity wholly without manual intervention and the jaws will move inwardly until the teeth on the jaws are automatically positively interlocked with the grooves in the grief stem. The hoisting cable is then slackened or released from the lifting bail in a well known manner and the load or weight of the rod line will be held by the hydraulic feed piston, and upon suitable manipulation of the control valve the feed piston and rod line` may be fed at the desired speed. During feeding movement of the drill rod the latter is rotated and the members 31 of the chuck each cooperate with the longitudinal grooves 33 on the grief stem to permit the grief stem and drill rod to rotate together. When soft formations are encountered and a core is not required, the core barrel is removed from the rod line anda fishtail or rotary bit substituted therefor. During drilling with the ishtail bit either the hydraulic feed or hoisting cable is used, the hoisting cable being connected to the lifting bail 22 and the grief stem fed by the hoisting drum. The collar 38 of the automatic chuck is then moved upwardly, releasing the teeth on the jaws from the grooves in the grief stem and the jaws locked in this released position by the pin and slot connections. The drill rod is then rotated and as the tishtail bit penetrates the soft formation it is fed downwardly by either the hydraulic or the hoisting drum and cable. These and other operations ot the improved drilling apparatus will be clearly apparent to those skilled in this art.

As a result of this invention an improved unitary and compact drilling apparatus is provided wherein either a diamond core bit or a tishtail or rotary bit may be selectively used when hard or soft formations are en countered. It will further be noted that an improved automatic chuck is provided of an exceedingly simple andcompact character which positively engages the grief stem during the hydraulic feeding of the bit, which may be applied and released with facility, and which may be readily locked in its released position in an improved manner.

While I have in this application specifically described one form which my invention may assume in practice, it will be understood that this form of the same is shown for purposes of illustration and that the invention may be modified and embodied in various other forms withoutdeparting from its spirit or the scope of the appended claims.

lVhat l claim as new and desire to secure by Letters Patent is:

1. A grief stem chuck for a drill feeding mechanism of the character wherein a grief stem with teeth is employed comprising means for engaging a grief stem to rotate the latter, and means 'for connecting the chuck to a grief stem including chuck jaws having teeth engageable with teeth on a grief stem, said jaws having inclined surfaces, and means for actuating said jaws into interlocking engagement with a grief stem comprising a member having inclined surfaces engaging the inclined surfaces on said jaws.

2. A grief stem chuck for a drill feeding l mechanism of the character wherein a grief stem with teeth is employed comprising means for engaging a grief stem to rotate the latter, and means for connecting the chuck to aA grief stem including chuck jaws having teeth engageable with teeth on a grief stem, said jaws having inclined surfaces. and means for actuating said jaws into interlocking engagement with a grief stem comprising a slidable member surrounding said aws and having inclined surfaces engaging the inclined surfaces'jon said jaws.

3. A grief stem adapted for drilling purposes comprising a body generally cylindrical in cross section and having longitudinally extending grooves forming spaced longitudinal projections and a plurality of series of closely spaced transverse teeth formed on said projections.

4. A grief stem adapted for drilling purposes comprising a body generally cylindrical in cross section and having longitudinally eX- tending grooves forming spaced longitudinal projections and a plurality of series of closely spaced transverse teeth formed on said projections, said series of closely spaced teeth being located at points spaced at substantial intervals longitudinally of the stem. 5. A grief stem chuck for a drill feeding mechanism of the character wherein a grief stem with teeth is employed comprising a body having means for engaging and rotating a grief stem, and means for connecting the chuck to a grief stem including chuck jaws slidably mounted in said body, each having a series of teeth engageable with a series .of teeth on a grief stem, said jaws having inclined surfaces, and means for actuating said jaws to cause the same to move inwardly into interlocking engagement with a grief stem, comprising a collar surrounding said body and having inclined surfaces cooperating with the inclined surfaces on said jaws.

.6. A grief stem chuck for a drill feeding mechanism of the character wherein a grief stem with teeth is employed, comprising a body having means for engaging and rotating a grief stem, and means for connecting the chuck to a grief stem including chuck jaws slidably mounted in said body and having a series of teeth engageable with a series of teeth on a grief stem, said jaws having inclined surfaces, and means for actuating said jaws to cause the same to move inwardly into interlocking engagement with a grief stem, comprising a collar surrounding said body and having inclined surfaces cooperating with said inclined body surfaces and movable in one direction to eect locking of said jaws with the stem, and members carried by said collar slidably engaging grooves in said jaws for causing release thereof when said collar is moved in an opposite direction.

7. A grief stem chuck for a drill feeding mechanism of a character wherein a grief stem with teeth is employed comprising a body having formed thereon a key portion engageable with a longitudinally extending groove on a grief stem for rotating the latter,

and means for connecting the chuck to a grief stem including chuck jaws adjustably mounted in said body, said jaws each having a series of teeth engageable with a series of teeth on the grief stem and inclined surfaces, and means for actuating said jaws to cause the same to move inwardly into interlocking engagement with a grief stem comprising a reciprocable member surrounding said body and having inclined surfaces cooperating with said inclined jaw surfaces.

8. A grief stem chuck for a drill feeding mechanlsm of the character wherein a grief stem with teeth is employed comprising a body having a key portion engageable with a longitudinally extending groove formed on a grief stem for rotating the latter, and means for connecting the chuck to a grief stem including chuck jaws adj ustably mountf ed in said body, said aws each having a series of teeth engageable with a series of teeth formed on the grief stem and 4inclined surfaces, and means for actuating said jaws for moving the latter into interlocking engagement with the grief stem comprising a slidable collar surrounding said body and having inclined surfaces engaging said inclined jaw surfaces, said collar being movable in one direction to lock the jaws to the stem, said collar also having members engageable with grooves formed on said jaws for causing release of said jaws when said collar is moved in an opposite direction.

9. A grief stem chuck for a drill feeding mechanism of a character wherein a grief stem with teeth is employed comprising a body having means for engaging and rotating a grief stem, and means for connecting the chuck to a grief stem including chuck jaws slidablymounted in said body, said jaws each having a series of teeth engageable with a series of teeth on a grief stem, means for moving said jaws inwardly into interlocking engagement with the grief stem and for releasing said jaws, and means for locking said jaws in their released position.

10. A grief stem chuck for a drill feeding mechanism of the character wherein a grief stem is employed comprisin a body having means for engaging and rotating a grief stem, and means for connecting the chuck to a grief stem including chuck jaws slidably mounted in said body and adapted to engage positively a grief stem, a member movable relative to said body and engageable with said jaws for moving the same inwardly into engagement with the grief stem and for releasing said jaws, and means carried by said member and engageable with said jaws for locking the same in their released position.

11. A grief stem chuck for a drill feeding mechanism of the character wherein a grief stem is employed comprising a body having means for engaging and rotating a grief stem, and means for connecting the chuck to a grief stem including chuck jaws slidably mounted in said body. and means movable relative to said body for causing said jaws automatically to engage positively a grief stem, said means being manually operable to eii'ect release of said jaws.

12. A grief stem chuck for a drill feeding mechanism of the character wherein a grief stem is employed comprising a. body having means for engaging and rotating a grief stem, and means for connecting the chuck to a grief stem including chuck jaws slidably mounted in said body, means movable relative to said body for causing said jaws automatically to engage positively a grief stem, said means being manually operable to effect release of said jaws, and means for locking said jaws in their released position.

13. In a drilling apparatus, the combination with a drive rod and means for rotating and longitudinally moving said drive rod, of an automatic chuck mechanism carried by said drive rod and adapted to engage positively a grief stem to connect the stem to said drive rod for longitudinal movement therewith, said chuck mechanism automatically engaging the stem upon relative longitudinal movement between said chuck mechanism and the stem.

14. In a drilling apparatus, the combination with a hollow rod, a thrust head carried by said rod, a drive rod rotatably mounted within said thrust head, and means for rotating said drive rod and for longitudinally moving said hollow rod to move said drive rod longitudinally, of an automatic chuck mechanism carried by the lower end of said drive rod and adapted to engage positively a grief stem to connectthe latter with said drive rodl for longitudinal `movement therewith, said chuck mechanism automatically engaging the grief stem upon relative longitudinal movement between said chuck mechanism and the stem. l

15. In a drilling apparatus, the combination with a drive rod, and means for rotating and longitudinally moving said rod, of a chuck mechanism carried by the lower end of said drive rod and adapted to connect positively a grief stem to said drive rod for lon gitudinal movement therewith, said chuck mechanism including jaw elements adapted to connect automatically the grief stem to said drive rod upon relative longitudinal'movement between said chuck mechanism and the grief stem. n

16. The combination of a grief stem adapted for drilling purposes having longitudinally extending grooves formed thereon and a plurality of series of circumferentially ex tending grooves, and a chuck mechanism comprising avbody through which said grief stem extends and having means engaging ,the y longitudinally extending grooves on said stem for rotating the latter, and means for connecting the chuck to the grief stem including chuck jaws slidably mounted in said body, each ofsaid jaws having a series of teeth adapted to interlock with the circumferentially extending grooves on said stem, and means for moving said jaws inwardly into engagement with said stem and for releasing said jaws.`

17 The combination of a grief stem adapted for drilling purposes having longitudinally extending grooves formed thereon and a plurality of series of circumferentially extending grooves, and a chuck mechanism comprising a body through which said grief stem extends and having means engaging the 1ongitudinally extending grooves on said stem for rotating the latter, and means `for connecting the chuck to the grief stem including chuck jaws slidably mounted in said body, each of said jaws having a series of teeth adapted to interlock with the circumferentially extending grooves on said stem, means for moving said jaws inwardly into engagement with said stem and for releasing said jaws, and means for locking said jaws in their released position.

18. The combination of a grief stem adapted for drilling purposes having longitudinally extending grooves formed thereon and a plurality of series of circumferentially extending grooves, and a chuck mechanism comprising a body through which said grief stem extends and having means engaging the longitudinally extending grooves on said stem for rotating the latter, and means for connecting theiehuck to the griet stem including chuck jaws slidably mounted in said body, each ot said jaws having a series of teeth adapted to interlock with the circumferentially extending grooves on said stem, means for moving said jaws inwardly into engagement with said stem and'for releasing said jaws, and means comprising elements carried by said means adapted to cooperate with grooves formed in the upper surfaces of said jaws for locking the latter in their released position.

19. The combination of a grief stem adapted for drilling purposes having longitudinally extending grooves formed thereon and a plurality of series ot circumterentially ex tending grooves, and a chuck mechanism comprising a body through which said grief stem extends, said body having key portions cooperating with said longitudinally extending grooves for rotating the stem, chuck jaws slidably mounted in said body each having a series of teeth adapted to interlock with the circumferentially extending grooves on said grief stem, and means for moving said jaws inwardly into engagement with said stem and for releasing said jaws.

, 20. The combination of' a grief stem adapted for drilling purposes having longitudinally extending grooves formed thereonand a plurality of series oi circu-mferential'ly extending grooves, and a chuck mechanism comprising a body through which said griet stem extends, said body having key portions cooperating with said longitudinally extending` grooves for rotating the stem, chuck jaws slidably mounted in said body each having a series of teeth adapted to interlock with the circumferentially extending grooves on said grief stem, and means for actuating said jaws comprising a collar surrounding said body and engaging said jaws for moving the latter inwardly into engagement with said stem and for releasing said jaws.

21. The combination with a longitudinally movable and rotatable drive rod, of a grief stem having longitudinally extending grooves formed thereon and a plurality of series of circumterentially extending grooves, and a chuck mechanism including a body lixed to said drive rod for movement therewith and through which the grief stem extends, said body having means engaging the longitudinally extending grooves on the grief stem for rotating the latter, and `means for connecting the chuck mechanism to the grief stem including chuck jaws slidably mounted in said body each having a series of teeth adapted to interlock with the circumferentially extending grooves on said stem, and means :tor moving said jaws inwardly to connect positively the stem to said chuck mechanism and for releasing said jaws.

22. The combination with a longitudinally movable and rotatable drive rod,of a grief stem having a plurality of series of circumferentially extending grooves formed thereon, and a chuck mechanism carried by said drive rod including means adapted to interf lock with the grooves on the grief stem for automatically positively connecting the grief stem to said rod for movement therewith when a series of grooves on the stem assume a predetermined position` withinl said chuck mechanism. t n j 23. In a drilling apparatus, the combination with a longitudinally movable feeding element, a drive rod actuated by saidfeedihng element, and means for rotating said driye rod, of a grief stem movable through said drive rod and having formed thereon a plurality of circumferentially extending grooves,l

said grooves being spaced apart longitudinally of said stem a distance corresponding to the distance of travel of the feeding element,

and a chuck mechanism carried by the lower end of said drive rod and having means for rotating the grief stem, said chuck mechanism including a plurality of jaws each having a projecting tooth thereon and means for moving said jaws inwardly to insert the teeth thereon within one of the grooves on said stem to connect positively the latter to said drive rod for movement therewith. j

24. The combination with a. drive rod, and means for rotating and longitudinally moving said drive rod, of a grief stem extending through said drive rod, a chuck mechanism carried by said drive rod adapted to connect rigidly and positively said grief stem to said drive rod and including an element in said v chuck abutting a transverse shoulder on said stem, and means whereb move freely through sai release of said chuck while stem is continued.

25. A grief stein chuck for a drill feeding mechanism comprising a body having means for engaging and rotating a grief stem, said body havinga central opening through which a grief stem is adapted to extend, and means for connecting the chuck to a griet` stem in cluding radially movable chuck jaws mounted within said body, and means including a member surrounding said body and movable relative thereto for moving said jaws.

26. A grief stem chuck for a drill feeding mechanism comprising a body having means for engaging and driving a grief stem, said body having a central opening through which a grief stem is adapted to extend, and means for connecting the chuck to a grief stern including radially movable chuck j aws carried by said body, and means including an operator controlled operating member surrounddrive rod upon rotation of said lmovable and rotatable drive said stem may ing 'said body and movable relative thereto for actuating said jaws. j

27. A grief stem chuck for a drill feeding mechanism comprising a body having means for engaging and" driving a 'grief stem, said body having a central opening through which agiiefstem s adapted to extend, and means or connecting the chuck to a grief stem including radially movable chuck jaws carried by said body, and means includingan operating member sui-rounding said body and movable relative thereto for actuating said jaws,.said jaws having wedge surfaces engageable by wedge surfaces on said operating member. l v l y, j 28.` In a drilling apparatus, the combination with a drive rod and means for longitudinally moving said drive rod, of an automaticchuck mechanism adapted to engage a grief stem to connect they stem to said drive rod, said chuck mechanism automatically engaging the stem upon relative longitudinal movement between said chuck lmechanism and the stem.

29. vIn a drillingv apparatus, the combination with a hollow rod, a thrust head carried thereby, a drive rod rotatably mounted within said thrust head and extending downwardly through said hollow rod, and means for longitudinally inovingsaid hollow rod, o t an automatic chuck mechanism carried by the lower end of said drive rod and adapted to engage a grief stem toconnect the latter with said longitudinally movable rod for movement therewith, said chuck mechanism automatically engaging the stem upon relative longitudinal movement `between said vchuck mechanism and the stein.

30. The combination with a longitudinally rod and a grief stem extending axially through said drive rod, of a chuck mechanism carried by said drive rod at the lower end thereof and through which the grief stem extends, said chuck mechanism including means for automatically operatively connecting the grief.

stem to said drive rod for movement therewith when said stem assumes a predetermined position within said chuck mechanism.

v31. The combination with a longitudinally movable and rotatable driverod, of a grief stem having a plurality of circumferentially extending grooves formed thereon and a chuck mechanism carried by said ydrive rod and -through which the grief stem extends, said chuck mechanism including means for automatically positively connecting the grief stem to said drive rod :tor movement therewith when a groove on the stem assumes a predetermined position within said chuck mechanism.

32. A grief stem chuck for adrill feeding mechanism of the character wherein a grief stem is employed comprising a body having formed thereon a key portion engageable with a longitudinally extending groove on a grief stem for rotating the latter, and chuck means carried by said body for engaging a griet stem for locking said stem and body t0- gether.

33. A grief stem adapted for drilling purposes comprising a body generally cylmdrical in cross section and having longitudinally extending grooves forming spaced longitudinal projections, and a plurality of transverse teeth formed on said projections.

34. In a drilling apparatus, the combination with a drive rod and means for moving the same longitudinally, of an automatic chuck mechanismadapted to engage a grief stem to connect the stem to the drive rod, and a grief stem passing through said chuck mechanism, said chuck mechanism and grief stem having portions adapted for connection When in predetermined relation to each other and said chuck mechanism having means for automatically effecting such connection when said predetermined relation is attained.

In testimony whereof I aiiix my signature.

- HARRY C. JOHANSEN. 

